PQ60033QPA45 Datasheet, PDF (12/14 Pages) SynQor Worldwide Headquarters – Quarter-brick DC/DC Converter

Technical Specification
Input: 35-75 V
Output: 3.3 V
Current: 45 A
Package: Quarter-brick
Over-Temperature Shutdown: A temperature sensor on the
converter senses the average temperature of the module. The
thermal shutdown circuit is designed to turn the converter off
when the temperature at the sensed location reaches the Over-
Temperature Shutdown value. It will allow the converter to turn on
again when the temperature of the sensed location falls by the
amount of the Over-Temperature Shutdown Restart Hysteresis
value.
This filter dramatically reduces input terminal ripple current,
which otherwise could exceed the rating of an external elec-
trolytic input capacitor. The recommended external input capac-
itance is specified in the “Input Characteristics” section. More
detailed information is available in the application note titled
“EMI Characteristics” on the SynQor website.
APPLICATION CONSIDERATIONS
Input System Instability: This condition can occur because
any DC/DC converter appears incrementally as a negative
resistance load. A detailed application note titled “Input
System Instability” is available on the SynQor website
(www.synqor.com) which provides an understanding of why
this instability arises, and shows the preferred solution for cor-
recting it.
Application Circuits: Figure D below provides a typical cir-
cuit diagram which details the input filtering and voltage trim-
ming.
Input Filtering and External Capacitance: Figure E below
provides a diagram showing the internal input filter components.
Vin(+)
Vout(+)
Electrolytic
Vsense(+)
Vin
External
Input
Capacitor
47µF
ON/OFF
R_trim-up
Trim
or
Filter
Vsense(^_)
R_trim-down C_load
I_load
Vin(^_)
Vout(^_)
Figure D: Typical application circuit (negative logic unit, permanently enabled).
L
Vin(+)
C
Vin(^_)
Figure E: Internal Input Filter Diagram (component values listed on page 3).
Product # PQ60033QPA45
Phone [phone]
www.synqor.com
Doc.# 005-2QP633F Rev. C
9/21/07
Page 12